recommend_fixtures

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It does state that the tool is deterministic and always runs, and it lists the return items. However, it does not mention potential side effects, error conditions, or prerequisites (e.g., whether geometry must be imported first). This is partial but not comprehensive for a complex sizing tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise, with three sentences that front-load the core purpose and then list outputs and a key parameter. It is well-structured and does not waste words, though the pointer to an external doc adds a minor dependency.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (16 parameters, no annotations, no schema descriptions), the description is insufficient for an agent to call it correctly. It lacks parameter semantics, usage conditions, and behavioral details such as required inputs or error handling. The external reference to workflow F is not self-contained, and the agent would likely need to consult external docs to use it effectively.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema has 0% description coverage for its 16 parameters, so the description must compensate. It only explains the 'distribution' parameter (direct|direct_indirect|indirect) and hints at 'mel-DER circadian' relating to target_mel_edi. The vast majority of parameters (e.g., rho_wall, maintenance_factor, target_efficacy_lm_w) are not explained at all, leaving the agent to guess their meaning and units.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states it performs fixture sizing using a combined lumen method and circadian solve, and lists the outputs (flux, count, layout, CCT band, energy, caveats). It is specific enough to distinguish from sibling tools like circadian_metrics or spd_to_channels, though it does not explicitly name an alternative. The purpose is unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no explicit guidance on when to use this tool versus alternatives. The phrase 'See operating-guide.md workflow F' points to external documentation but does not describe conditions or trade-offs. The description does not mention when to use this over, say, presets or compliance, leaving the agent to infer usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.